Study of fast energy electron beam profile monitor system

In the experimental study of accelerator physics, a turn by turn monitoring of the beam profile CAN provide very unique information. In this paper, we proposed a method which may measure a turn by turn electron beam profile through its synchrotron radiation by using a fast photo-diode. Here, we utilized the non-linearity of the response of the photo-diode detector. At high photon intensity, non-linearity occurred due to the saturation of the device. In this paper, we will present the theory and the test experimental results. We had examined this idea by using a modulated He-Ne laser to simulate the synchrotron radiation light. The results agree with our computer simulation results. But the photon power intensity of synchrotron radiation in the storage ring of TLS (Taiwan Light Source) is not sufficient to saturate the photo-diode as what we expected. In order to utilize the idea on the synchrotron radiation, we used an external light source to saturate the photo-diode and the synchrotron radiation be the probe beam. In this paper, the theory and the experiment of the above idea will be discussed